1. Field of the Invention
The present invention relates to polarized-light measurement apparatuses for measuring optical rotation and optical rotatory dispersion, and in particular, to an improvement in the spatial resolution thereof.
2. Description of the Related Art
Many biological substances exhibit characteristics whereby the plane of polarization of linearly polarized light transmitted through the substance is rotated (this effect is known as optical activity). Measurement of the optical activity is carried out to analyze the three-dimensional structure of substances. Apparatuses used to measure the optical activity or the wavelength dependence thereof (called optical rotatory dispersion) are known as optical activity spectrometers or optical rotatory dispersion spectrometers, respectively (for example, see Japanese Unexamined Patent Application Publication No. S55-103434).
However, with the optical activity spectrometers and optical rotatory dispersion spectrometers mentioned above, similarly to standard optical measurement apparatuses, it is not possible to perform measurement at scales smaller than the wavelength of the light used for measurement. In other words, similarly to other optical measurement apparatuses, there is a limit to the spatial resolution due to the diffraction limit of light.